Abstract: A design scheme of monitoring system of power station based on serial communication was proposed and software and hardware designs of sending part and receiving part and communication setting of the system were introduced in details. In the system, PLC is the controller of sending part to realize functions of collection, processing and control of parameters of power station and rotary UPS, PC is used as receiving part to realize functions of remote measurement, remote signaling and remote control of power station through VB program, and PLC communicates with PC through serial communication port. Besides, special designs are adopted in the system in terms of task protection, maintain and operation. The application showed that the system is simple in operation and reliable in performance.